Here’s how Chipotle spells out the online-only process in its press release: You have to create an account on the Chipotle mobile app. Then place your order online, say for a burrito or guacamole and chips. (You can get either added guac or a side of guac or guac and chips free when you buy an entree.) Then punch in guacamole as an add-on. Then plug in the offer code, AVOCADO, and the charge for guac should disappear from your order. Then you may approach the counter.

As the price of added guac has gone up, so have the savings. Added guac runs about $2.20 these days at most Bay Area Chipotle locations.